Joint for tubular frame members



March 31. 1925. 1,531,962'.

J. L ,LoYD JOINT FOR"TBULAR FRAME MEMBERS Fmg Deo.. 1s.' 1923 s sneersfspm 2 Patented Mar. 31, 1925.

UNITED STATESY l1,531,962 PATENT OFFICE.l

JOHN LLOYD, OF COVENTRY, ENGLAND, ASSIGNOR T ARMSTRONG SIDDELEY MOTORS LIMITED, 0F COVENTRY, ENGLAND, A BRITISH COMPANY.

JOINT FOR TUBULAR- FRAME MEMBERS.

Application filed December 13, 1923.

To @ZZ ctv/0m it may concer/n.:

Be it known that l, JOHN LLOYD, a subject of the King of England, residing at Coventry, in the county of Warwick, England,

have invented certain new and useful Improvements in Joints for Tubular Frame Members, of which the following is a specification.

This invention relates to joints for tubul0 lar frame members, of the kind in which one element of the joint encircles the other in the form of a sleeve, clip or socket forming part of or having attached to it other frame members, such as struts, ties or brackets, and it is particularly intended for use in uniting together the various members employed for the framework of aircraft or for the securing to the spars or otherA frame members of lugs, clips, brackets or the like.v y

It is the obj ect of the invention to provide a form of joint which, while of an exceedingly simple, light, and relativelj7 inexpensive kind, wholly avoids the necessity forbrazing,

Y welding or the like and has a strength which is considerably above that which wouldvbe inferred from a consideration of the stresses to which the joint is subjected. i

In the accompanying drawings which illustrate the manner of carrying out the invention,

Figure 1 is an end elevation of a spar or like tubular member for use uponI aircraft, to which are secured by the improved jointing means lugs for the attachment of a strut with a tie-rod on each side of it, as well 'as one or more socket pieces each carrying another tubular member,

Figure 2 is a plan as seen from above omitting for clearness certain port-ions,

Figure 3 is a side elevation as seen from the right of Figure l,

Figure 4 is an enlarged view of the fas-v tener in its normal condition, l

Figure 5 is a corresponding view of the fastener showing in a considerably exaggerated manner the form it assumes under stress at the joint,

Figure 6 is a side elevation of 'a simpler form of joint than that shown in Figures L3, having certainmodifications in its parts, Figure 7 is an end view of Figure 6, and

Figure Sis ka yfurther modified form of thc joint. suitable for useat the extreme end ,of

the tubular member. I

Serial No, 680,449.

Around the' tubularmember A is a sleeve B split at B2 in the axial direction. Encir cling the split sleeve is a clip C, C2 Aof sheet metal formed in two parts and provided with lugs C3, C4, by means of which the sides of the clip can be drawn together by rivets C, the lugs being provided with eyes at C7, C8 and C9 for attachment thereto of the above mentioned struts and tie-rods. An additional eye C10 vis also shown vas part of the lugs C4. i j

The fasteners which secure the splitsleeve and the lug to the member A are in the form of rods D screw-t-hreaded at each end D2, and there provided with nipples having` a head E of hexagonalor other non-circular form and a plain cylindrical bodv E2 adapt4 ed to fit in holes E3 drilled completely through the. elements of the oint from side to side at suitable positions along it, or around it. The nipples are tightened up so that the heads bear against the outer faces of the' split sleeve B and the clip C respectively, (see Figure t) and may be further secured by lock nuts.

The fasteners thus prevent both axial and rotational movement of the joint, and in re-v sisting the axial or the rotational'stresses upon the joint the rods D bend slightly and tiltthe nipples so that their heads tend to rise slightly upon one side and to be more firmly compressed on the` other side, thus producing the pinching effect which is thel feature of the invention, (see Figure 5, in which the bendingv effect is considerably exaggerated).

Figures l-3 also illustrate the application of the invention to asocket joint-where a second tubularframe member F pro-vided with aV liner F2 similar to B is secured in a socket G'by the fasteners D as just described. The socket itself may be provided with jaws G2 adapted to embrace an eye H 2'on a stem H 'extending completely through the joint and securedby a nut H2. A pin or other fastener H4 extends through the jaws G2 and the eye H2, thereby providing a hinge connection for the tube F. Stifi'ening plates H5 and H6 encircling the clips C, C2, with lugs Hf and HS lying against the lugs C2 and C4 respectively reinforce the latter and givev the necessary strength for.' attachment required. j j v v In Figure l are shown three other sockets J, K, and L, each for a tubular member, the

socketsd and K being directly hinged to the lugs C3 and C4 and the lugs H7 and IIB respectively of the` clip C andstifening plates H5, I-IG, while the ysocket L is provided with It will be seen that with the sockets J, and L the split sleeve corresponding to B' and F2 is omitted from the joint, as in cer tain' cases itis not necessary.

The form of'joint shown in Figures 6 and 7 Vis of a simpler naturerth'an the foregoing but retains the ksplit sleeve B securedasbe fore to the tubular member A. The clip N which encircles the sleeve B is made in one partV with'lugs at Ng'wide enough to' provide for three eyes N1", NA1` and N for'attachment of stays or struts, one of the latter being illustrated at N4. The clip on the side opposite `to the lugs N2 is made only as wide as is necessary for strength, and the fasteners D'extend as beforethrough all three members as `well as through the sleeve B and member A` only. Rivets N serve to unite the clip together and` also to secure upon it reinforcing and thickening plates 0,' O2, to' enable the socketP Afor the strut P2 to be hinged to the eye NL in asubstantial manner by means: of the hinge pin P3.

In Figure 8, the tubular member A is provided withthe split sleeve B at its end, the :ends ofthe sleeve and of the member A being level with one another. A hollow plug Q having" a flange QF extends intovand closesl the end of the tubular member and provides for the attachment thereto' of'a' jaw portion R secured to the plug Qby means of a threaded stem R2, and provid# ing thereby for the attachment ofstay fas' tenings S, To the awed portion R may be hinged the socket TL of a strut T as inr previous arrangements. Surrounding the sleeve B isa clip U closely resembling the clip Y (Figures 6 andv?) but of aY simpler forni.l This is also arranged to haveconnectedto it a tubular member V. Furthermore, by means of a screwed stem IV extending through the clip U, sleeve B, tubular member A and' hollow plugQ, other stays may be attached, as in the manner shown in Figures 1-3.

It will be understood 4that the spacing of Y the fasteners I) along and'around the ele- 'ments of the'jointr` will be such as` to cause M2, M3 and MAL suitably bentA are pinched tightly together and thei'rlfric tional engagementlis very greatly` increased. In this way the joint will then withstand loads -in excessof that which would be anticipated by a calculation based upon-the dimensions and the `nature of the material employed in its constitution;L Y

Although the fastener D is preferablyformed in-the'manner above described, it will be obvious that the nipple at one end might be formed integrally withthef bodyj of the rod. The construction illustrated, however, isequally satisfactoryv and less expensive.4

hat I claim as my invention and desire to secure by Letters Patent-of th'efUnited States is l. In a joint for tubularfframe members,

the combinationof a tubular memberl forming one elementfofithe` joint, vajp'art encircling said'tubular member formingthe sec-s ond relement of-said joint, afa'stener-extendi ing completely through both' elements,. af head ateach"v end of said fastener' which bears against said second element,`and a neck portion under each headI of greater cross sectionalv area than said fastener, thereby toy permit tilting of said' head and neck portions through flexurev of said fastener under axial or twisting load upon the joint, substantially as set'forth.`

21. In a joint for tubular frame members, the'combination off a tubularmember form` ing one element of the joint, ap'art encircling said tubular member forming the. second element of saidjoint, a-fastener in the form of a rod extending completely through both elements, a' shouldered nipple' secured upon each end of" said'rod comprising a plain bod)7l part which extends through the wall of each element anda" head part which bears againstI the outer element secured upon each end of` said rod and relatively adjustable towards one another to bear against the outer lelement,.substantially as set forth.

3. In a joint for tubular frame members, the lcombination of a tubular.me1nb`erforming one elementv ofthe jointVa part= encircling said tubular memberE forming the second element ofl said `joint having attached to litv load-carrying members, a'4 fastener vex*- tending completely throughbothV elements comprising a rod, shouldered nipples screwthreaded thereon at each end, each having a body part which extends through the adjacent walls of each element and a head part which bears against the outer element, and

` means for looking said nipples when screwed up upon said rod, substantially as set forth.

In testimony whereof I have signed my name to thls specricatlon 1n the presence of two subscrlblng wltnesses.

tnesses S. J. MATES, H. G. C. WILSON.

JOHN LLOYD. 

